• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.7
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• pp.479-485
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• 2001

In this paper, we propose optical subcarrier mutiplexing(SCM) transceiver module for base station(BS) that has no optical source and can be used for full-duplex communication over single optical fiber. In this method we retransmit optical modulated signal to the central office(CO) using loop-back system with a ring type Mach-Zehnder modulator(MZM) in BS, where optical source is transmitted from the CO. We have modeled the ring type MZM and were conformed that the measured results were in good agreement with the modeling. In the ring type MZM, the optical symmetric position of the MZM is very important in RF signal transmission.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.1
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• pp.18-23
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• 2007

In this paper, LPDA standard antenna for measuring DTV signal strength is developed. Duralumin material is used to fabricate antenna having mechanical strength and flexibility. Operating frequency of designed antenna is range from $450{\sim}850$MHz and its gain is greater than 10 dBd to satisfy FCC requirements. Experimental results show that the developed antenna has minimum 10 dBd gain (average 11.7 dBd) over the entire frequency region and has ${\pm}1.5$ dB pass band ripple characteristic, From the results, the developed antenna is well adequate for standard antenna to measure DTV signal strength.

• Journal of Information Technology and Architecture
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• v.10 no.1
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• pp.93-100
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• 2013

The purpose of this paper is to present Smart Virtual TRS(Trunked Radio System) service that gives the TRS function in mobile network with smart phone application and server. TRS is essential equipment of logistics vehicle so, most of trunk drivers uses TRS frequently. Developed service is based on smartphone without TRS equipment. Therefore, Smart virtual TRS included in TMS(Transportation Management System) has some effects for logistics company. i) Smart Virtual TRS gives better communication environment between office and drivers. ii) Smartphone App gives flexibility to TMS functions. iii) Smart Virtual TRS gives cost reduction effect.

• The Journal of the Korea Contents Association
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• v.13 no.6
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• pp.125-136
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• 2013

Director Choi Donghoon is the most famous director in Korea as a box office successor, especially (2102) has gained No. 1 box office attraction in Korean film history. However some critics have criticised the works of Dr. Choi because of their plebeianness. This paper focused on the reason of interaction with audiences through the theory of carnival of Mikhail M. Bakhtin. Because the theory of carnival is not only the adapted method to account for the power of popular culture to M. Baktin but also the useful method to understand the keys of interaction of Dr. Choi's films. It's not difficult to find the esthetic elements of carnival theory example for 'dethronement & coronation', 'overturn & ridicule', 'image of feast', 'language of square' in the films of Choi which are The Big Swindle(2004), Tazza: The High Rollers(2006), Woochi(2009), The Thieves(2012). Therefore this paper has endeavored that the box office attraction and success of communication with audiences is due to the realistic attitude and social reflection of Choi's films.

• Journal of The Korean Dental Society of Anesthesiology
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• v.5 no.1 s.8
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• pp.15-21
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• 2005

Autism is characterized with an abnormality of reciprocal social relatedness and of communication development. Also, autistic children show repetitive and stereotypical behavior pattern and deficiency of endurance against change. Dental problems related to autism are self-injury and trauma from accidents. Sometimes self-injury is due to discomfort resulting from restoration and local anesthesia. Also, gingivitis and multiple caries are common because of poor oral hygiene. Autistic children are anxious about visual and auditory stimuli because they don't understand the dental procedure. If the face of any changes in their daily life, their behavior becomes uncontrollable. In a setting such as the outpatient office, an autistic child's uncontrollable behavior makes it difficult to carry out proper treatment. If they need treatment under general anesthesia, it is very difficult to manage them in a ward as they are severly anxious about being admitted to a hospital. Therefore it is necessary to treat these children according to a specific management program under general anesthesia in an outpatient office. This case study reports of a 14 year old autistic teenager who although became uncontrollable because of the pain from multiple caries and from anxiety of the dental treatment eventually received treatment under general anesthesia and under conscious sedation in an outpatient office.

• Safety and Health at Work
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• v.5 no.3
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• pp.118-124
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• 2014

Background: Satisfactory completion of mine safety training is a prerequisite for being hired and for continued employment in the coal industry. Although training includes content to develop skills in a variety of mineworker competencies, research and recommendations continue to specify that specific limitations in the self-escape portion of training still exist and that mineworkers need to be better prepared to respond to emergencies that could occur in their mine. Ecological models are often used to inform the development of health promotion programs but have not been widely applied to occupational health and safety training programs. Methods: Nine mine safety trainers participated in in-depth semi-structured interviews. A theoretical analysis of the interviews was completed via an ecological lens. Each level of the social ecological model was used to examine factors that could be addressed both during and after mine safety training. Results: The analysis suggests that problems surrounding communication and collaboration, leadership development, and responsibility and accountability at different levels within the mining industry contribute to deficiencies in mineworkers' mastery and maintenance of skills. Conclusion: This study offers a new technique to identify limitations in safety training systems and processes. The analysis suggests that training should be developed and disseminated with consideration of various levels-individual, interpersonal, organizational, and community-to promote skills. If factors identified within and between levels are addressed, it may be easier to sustain mineworker competencies that are established during safety training.

• Korean Journal of Remote Sensing
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• v.22 no.6
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• pp.595-600
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• 2006

GOCI is the core paryload of the geostationary satellite COMS(Communication, Ocean and Meteological Satellite) for ocean monitoring. It is scheduled to be launched at the end of 2008. GOCI observes ocean color around the Korean Peninsula over $2500km\times2500km$ area. It used tilted two-axis scan mechanism to observe entire field of view. In this work, the pointing stability of the tilted two-axis method is analyzed and compared with that of gimbal method. The analysis results show that tilted two-axis method gives great stability and it is adequate for geostationary payload. The results can also be used to determine and analyze the mechanism specifications.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.5
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• pp.105-118
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• 2009

In modern society, as the rapid development of IT technology combined with the computer-based high-speed communication networks makes it possible to provide a wide spectrum of services and devices, we have been confronting a new cultural transformation era, referred to as the information society. However, the requirements to be considered in security aspect have became more complicated and diversified, and there remains the same security weaknesses as in the existing media or protocol. Particularly, the office network device with roaming is susceptible to the different kinds of attacks such as terminal hacking, virus attacks, and information leakage because the computing capacity is relatively low and the loading of already developed security functions is difficult. Although developed as one solution to this problems, PKI security authentication technology isn't suitable for multi-domain environments providing uonments proffice network service, and so the development of a novel authentication system is needed. Therefore, in this paper researched the roaming and device authentication/auth for multitechnology using an ID-based public key, authorization ticket, and Sub-device ticket with a purpose to contribute to the development of the secured and efficient technology.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.4
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• pp.510-518
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• 2022

The diagnostic evaluation conducted at the national level is very important to detect underachievers in school early. This study used an artificial intelligence method to find the characteristics of underachievers that affect learning development for middle school students. In this study an artificial intelligence model was constructed and analyzed to determine whether the Busan Education Longitudinal Data in 2020 by entering data from the first year of middle school in 2019. A predictive model was developed to predict basic middle school Korean, English, and mathematics education with machine learning algorithms, and it was confirmed that the accuracy was 78%, 82%, and 83%, respectively, in the prediction for the next school year. In addition, by drawing an achievement prediction decision tree for each middle school subject we are analyzing the process of prediction. Finally, we examined what characteristics affect achievement prediction.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.4
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• pp.238-247
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• 2020

This study has a purpose to analyze quantitatively whether ICT industry provides the qualitative indicator of employment to attract excellent human resources. We investigate the relationships of labor market conditions among ICT manufacturing, non-ICT manufacturing, ICT services, non-ICT services. Therefore, the quantitative and qualitative indicators of employment (wages, working hours, admission and turnover, involuntary retirement, and the duration years of job) are analyzed for the ICT industry and IT workers. In order to quantitatively analyze qualitative indicators such as employment status and longevity, we used employment statistics. In order to compensate for the limitations of employment insurance data, the comparison analysis with the survey data of economically active population of the National Statistical Office was conducted. As a result of this research, ICT service industry has to improve the working conditions of employees and establish an ecosystem for a lifelong career base to grow as a specialist, need to pursue an investigation for ICT worker career shift, and promote standard labor contracts. In addition, protection of employees, ICT-related job vision and social respect have to be perused.